This patch enable to give a parameter to device tree to set the number of bits per word the DMA uses in transfer In device tree you can specify fsl,spi-dma-bits-per-word = <16>; in the ecspi section
Signed-off-by: Aurelien BOUIN <[email protected]> diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index f8400b2..9690d57 100644 --- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c @@ -110,6 +110,7 @@ struct spi_imx_data { u32 rxt_wml; struct completion dma_rx_completion; struct completion dma_tx_completion; + unsigned int dma_bits_per_word; const struct spi_imx_devtype_data *devtype_data; int chipselect[0]; @@ -825,6 +826,7 @@ static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx, { struct dma_slave_config slave_config = {}; int ret; + enum dma_slave_buswidth dsb_default = DMA_SLAVE_BUSWIDTH_1_BYTE; /* use pio mode for i.mx6dl chip TKT238285 */ if (of_machine_is_compatible("fsl,imx6dl")) @@ -837,10 +839,20 @@ static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx, ret = -EINVAL; goto err; } - + switch (spi_imx->dma_bits_per_word) { + case 32: + dsb_default = DMA_SLAVE_BUSWIDTH_4_BYTES; + break; + case 16: + dsb_default = DMA_SLAVE_BUSWIDTH_2_BYTES; + break; + default: + dsb_default = DMA_SLAVE_BUSWIDTH_1_BYTE; + break; + } slave_config.direction = DMA_MEM_TO_DEV; slave_config.dst_addr = res->start + MXC_CSPITXDATA; - slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + slave_config.dst_addr_width = dsb_default; slave_config.dst_maxburst = spi_imx_get_fifosize(spi_imx) / 2; ret = dmaengine_slave_config(master->dma_tx, &slave_config); if (ret) { @@ -858,7 +870,7 @@ static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx, slave_config.direction = DMA_DEV_TO_MEM; slave_config.src_addr = res->start + MXC_CSPIRXDATA; - slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + slave_config.src_addr_width = dsb_default; slave_config.src_maxburst = spi_imx_get_fifosize(spi_imx) / 2; ret = dmaengine_slave_config(master->dma_rx, &slave_config); if (ret) { @@ -1083,7 +1095,7 @@ static int spi_imx_probe(struct platform_device *pdev) struct spi_master *master; struct spi_imx_data *spi_imx; struct resource *res; - int i, ret, num_cs; + int i, ret, num_cs, dma_bits_per_word = 8; if (!np && !mxc_platform_info) { dev_err(&pdev->dev, "can't get the platform data\n"); @@ -1138,6 +1150,11 @@ static int spi_imx_probe(struct platform_device *pdev) spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message; spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message; spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + if (of_property_read_u32(np, "fsl,spi-dma-bits-per-word", + &dma_bits_per_word)) + spi_imx->dma_bits_per_word = dma_bits_per_word; + else + spi_imx->dma_bits_per_word = 8; init_completion(&spi_imx->xfer_done); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
